A front-end circuit generically refers to a circuit or circuitry that provides an input to a back-end circuit. The front-end circuit typically supplies to the back-end circuit either a single-ended signal or a differential signal. A single-ended signal is referenced to a common voltage, and thus, the information contained in the single-ended signal is represented as the difference between the single-ended signal and the common mode voltage. A differential signal includes two inputs, each referenced to a common voltage. Therefore, the information carried by the differential signal is represented as the difference between the voltages of the two inputs.